Many modern microprocessors rely on external on-board voltage regulators (VRs) to measure the current and power consumed by the processor, memory, or other on-platform components. VRs are typically rated for a certain error, which is typically introduced due to component tolerances in high volume manufacturing of VRs. Thus, there are inaccuracies in the current or power readings delivered by the VR due to part-to-part manufacturing variation.
To avoid damage, a component should never exceed its power rating. Traditionally, a “guardband” is conservatively applied to the VR power readings when making power management decisions. For typical (not worst-case) scenarios, the guardband directly translates to a performance loss. For example, if a 100 W component is supplied by a VR with a +/−5% error in its power or current reporting capability, the component is effectively limited to 95 W to leave room for possible errors. Such a 5 W loss in available power implies a reduced peak performance for the component.
Additionally, the performance of a VR tends to go down over time. Thus, even assuming that a VR operates at a particular power, the available power can fluctuate as the VR ages. Such VR fluctuation can cause stress on the component that lessens its expected lifespan.
Descriptions of certain details and implementations follow, including a description of the figures, which may depict some or all of the embodiments described below, as well as discussing other potential embodiments or implementations of the inventive concepts presented herein. An overview of embodiments of the invention is provided below, followed by a more detailed description with reference to the drawings.